Joist hangers are support structures used for securing wooden joists onto beams. They are small-sized and are used to reduce vertical alignment issues underneath a floor frame. Joist hangers hold joists firmly in place and limit twisting and warping.
In residential construction, joists are used for transferring loads from floors and ceilings onto beams.
To do this, the joists themselves have to be correctly installed. There are two ways by which joists can be secured in a structural floor frame.
One is to have the joists rest directly onto beams. Although effective, this method of securing joists may lead to height difference issues.
The other way is to use joist hangers, by which joists can be hung onto beams.
This article aims to provide detailed information regarding what joist hangers are, what advantages they offer, their different types, and how to use them.
What are Joist Hangers? How they Work
Joist hangers are supporting aids that are used in residential construction to support and secure joists.
They function by allowing wooden joists and beams to be hung onto bigger beams.
Joist hangers are used extensively underneath floors and ceilings to create a strong connection between joists and a beam.
Having joists rest directly onto beams allows them to develop twisting and warping over time.
To help avoid this problem, joist hangers are utilized.
Joist hangers keep joists tightly in place, thus restricting their movement and not allowing them to deform.
Therefore, by installing joist hangers, the structural integrity of the joists and consequently the floors and ceilings are preserved.
Joist hangers are installed over the edges and the sides of a beam and are fixed using galvanized nails and screws.
These hangers have connecting plates attached to them which are nailed into the joist and beams to make a rigid connection.
In addition to being nailed and screwed, joist hangers can also be welded, making them more versatile to use.
They have an easy installation process and are very cost-effective over time.
How Much Weight can Joist Hangers Support?
Joist hangers are designed by taking into consideration the size and weight of the joists that have to be installed.
2×6 joist hangers have a minimum vertical bearing capacity of 305 lbs, while 2×8 joist hangers can hold a minimum of 540 lbs.
Similarly, 2×10 joist hangers can hold a minimum weight of 605 lbs, while 2×12 joist hangers can have a minimum capacity of 850 lbs.
Joist Size | Minimum Capacity (lbs) |
---|---|
2×6 | 305 |
2×8 | 540 |
2×10 | 605 |
2×12 | 850 |
Joist Hanger Vertical Weight Capacity*
*Minimum capacity of joist hangers can vary depending on the brand and design.
Applications of Joist Hangers
Joist hangers are used to help attach wooden joists onto wooden beams.
Additionally, they can be used to attach joists to masonry walls.
They have an easy installation process and can be installed using nails, screws, or by being welded.
Joist hangers are primarily used when having joists rested onto beams causes vertical headspace problems.
Using joist hangers increases the uniformity of the floor and reduces height alignment issues, making it more aesthetically pleasing.
They come in various shapes and sizes and are galvanized so they can be used for outdoor purposes as well.
Joist hangers are cheap and very cost-effective.
Types of Joist Hangers: 2 Types
Joist hangers come in all sorts of shapes and sizes but are of two primary types.
Connection | Type |
---|---|
Timber to Timber | Mini joist hanger |
Timber to Timber | Long-leg joist hanger |
Timber to Timber | Heavy-duty joist hanger |
Timber to Timber | I-joist hanger |
Timber to Masonry | Welded masonry joist hanger |
Timber to Masonry | Welded masonry return joist hanger |
One is the timber-to-timber joist hanger used for connecting wooden joists to wooden beams.
The other is the masonry-to-timber hanger joist used to connect wooden joists to masonry walls and posts.
There is also a universal joist hanger which is a multifunctional joist hanger and can be used in place of any joist hanger.
Further classifications of the above-mentioned types have been discussed below.
Timber-to-Timber Joist Hangers
These joist hangers provide a fast and efficient way to fasten wooden joists onto wooden beams and boards.
They are easy to nail, with mostly no drilling requirements.
Some types of timber-to-timber joist hangers are listed below.
Mini Joist Hanger
This joist hanger is primarily used for resisting light loads, such as loads of flat ceiling joists, and light floor joists.
Mini joist hangers come in widths of up to 78mm and can have depths of up to 100mm.
Long-Leg Joist Hanger
This joist hanger is designed to carry large loads. They are used for making connections between heavy joists and beams.
They restrict any unnecessary rotation in the joists.
Long-leg joist hangers come in three sizes depending on the length of their legs.
The short ones are about 210mm long, the standard ones are about 300mm long and the long ones come with a length of 600mm.
Heavy Duty Joist Hanger
As the name suggests, these joist hangers are used for supporting even heavier joists.
These joist hangers can be nailed or bolted and must support the member with an effective depth of at least 60% of the face of the member.
These joist hangers can also support large beams and trusses.
These joist hangers are used explicitly for securing I-joists onto the face of wooden beams.
They must utilize their full depth to restrict the movement of I-joists and avoid any rotation.
Timber-to-Masonry Joist Hangers
These joist hangers are used to make connections between wooden joists and masonry walls.
The use of masonry joist hangers eliminates the need for drilling extra support holes in the masonry walls.
Following are some types of timber-to-masonry joists that are extensively used in construction.
Welded Masonry Joist Hanger
These are the traditional joist hangers used for securing wooden joists.
The back of this joist hanger is welded into a masonry wall.
They provide excellent strength and grip for holding joists in place.
Welded Masonry Return Joist Hanger
Like the welded masonry joist hangers, these joist hangers are also welded into masonry walls for support but provide additional strength for holding joists.
The return hangers are designed such that they wrap around the lateral support which adds additional supporting strength.
Universal Joist Hangers
This joist hanger has the most versatility out of all the types and can be used to replace any of them.
It can form timber-to-timber, as well as timber-to-masonry connections.
How to Install Joist Hangers Properly
The first thing to do before using joist hangers is to carefully analyze and select the size of the joists that are to be installed.
It is also important that the beam or rim joist on which the joist will be hung are of sufficient size.
The sizing should thus only be done by a structural engineer.
Then select the type of hangers to be used accordingly.
The best method of connecting joist hangers on the sides of beams is by using screws or bolts.
Although galvanized nails are also available specifically for joist hanger plates, it is still better to use screws for a tighter grip.
Start the installation process by aligning the top of the joist to be installed with the top of the rim joist or beam.
Use a scrap of wood for aligning the tops and temporarily supporting the joists as shown in the figure below.
Now place a joist hanger in its position and keep a tight hold on the sides of the hanger by pressing on them.
Then hammer the two prongs of the hanger into the joist to temporarily support the hanger in place.
Now hammer nails or drill screws in the holes of the connecting plate to form a permanent rigid connection.
Start by nailing the rim side of the hanger first and then nail the joist side.
Be careful not to let any hole go empty for more efficiency.
If there is not enough space to use a hammer to nail the holes, then a pneumatic palm nailer can be used instead.
After nailing is complete, remove the piece of wood used for aligning the joists and your installation process is now finished.
Common Mistakes to Avoid when Installing Joist Hangers
The installation process of joist hangers is relatively easy however there are still some common mistakes that builders make while installing joist hangers
It is necessary to avoid these errors so as to ensure the structural integrity of the floor frame.
The size of the joist hangers is one of the most recurring factors that builders often get wrong.
It should be carefully selected taking into consideration the size of the joist and the beams.
Sometimes a few holes in the connecting plates are left empty which reduces the hanger efficiency for carrying loads.
In other instances, the fasteners used for fastening joist hangers are insufficient in size and number.
These mistakes should be avoided at all costs and the installation process must be done in accordance with the building codes.
The following steps can be adopted to avoid any incoherency in the installation process of joist hangers.
- The fasteners being used should be of the correct size.
- No nailing holes in the connecting plates should be left empty.
- The nailing should be done at an angle of 45 degrees to get the maximum grip.
- Galvanized nails should be used for exterior use.
- Joist hangers once used, should never be reused.
- Joist hangers should not be modified.
- The hanger height should be at least 60% of the joist height.
Corrosion Issue in Joist Hangers
Joist hangers used in basements and outdoor decks are likely to corrode over time due to being in contact with moist lumber.
The lumber used for joists can have corrosive effects on joist hangers which are made of steel and galvanized coatings.
To prevent corrosion, it is advised to use a higher-rated galvanized coating such as the G185 rather than using the normal G-90 or G-60 coatings.
Even G-185 coatings experience corrosion only after a few weeks of use, which then becomes visible on its edges.
Another alternative is to use stainless steel joist hangers which function better under varying weather conditions.
Fasteners for Joist Hangers
Usually, information regarding the fasteners required to fasten joist hangers is not given along with the joist hangers.
To get this information you have to consult the manufacturer’s load tables.
Cost of Joist Hangers
There is no fixed pricing for joist hangers because they come in a variety of shapes and sizes.
The average price for 2×6 joist hangers ranges between $10-$20, whereas, 2×8 joist hangers can be found for $25-$30.
Joist hangers are also available in bundles, which cost significantly less than buying a single joist hanger.
Conclusion
Joist hangers are very useful in residential construction for hanging joists onto beams and allowing a path for proper load transfer.
They can be used to connect wooden joists with wooden beams as well as with masonry walls and posts.
Joist hangers come in various sizes and shapes. They can be nailed, bolted, and even welded, which makes them very practical.
Having joists rest directly onto beams leads to height alignment issues, which can be avoided by using joist hangers.
It is very easy to install joist hangers, but care must be taken to avoid any mistakes.
The fasters used for fastening joist hangers should be of proper size and strength.
Frequently Asked Questions (FAQ)
Is it better to use joist hangers than to toe-nail joists directly onto beams?
Using joist hangers allows for more precise installation.
They also provide support on the underside of the joists which makes them stronger than toe-nailing.
Although joist hangers add to the cost of the overall project, they provide ease of installation and increased strength which makes them the better choice.
Can I use a 2×8 joist hanger for a 2×10?
Joist hangers can be used for the joist sizes mentioned on the box and the next size up.
This means that joist hangers that come for 2×8 joists have sufficient strength to be used for 2×10 joists as well.
But it is essential to check the load capacity of the hanger and the load of the joist to be sure.
How far apart should joist hangers be?
Joist hangers follow the spacing of the joists. Joist spacing is selected based on joist span, joist material, material grade, and the load acting on the joist.
On average the joist spacing underneath floors is kept at 12” to 16”, consequently joist hangers follow the same spacing.